The present invention generally relates to a swim training device, and more particularly, to an apparatus which can be used to exercise and practice the swimming technique generally known as the crawl or freestyle stroke.
A variety of sports training devices have been devised to facilitate in the training of individuals in the exercise and practice of various swimming techniques (i.e., strokes). The present description is primarily directed to one such stroke, that being the crawl or freestyle stroke. However, a similar approach may be used to facilitate in the training of individuals in other strokes, if desired.
There are a variety of situations in which it would be desirable to have the availability of a device that can either help teach a non-swimmer proper freestyle stroking form, or to allow a person with prior knowledge of the freestyle stroke to practice and/or to strengthen his or her form. For example, it may be desirable to allow a beginner to learn a freestyle stroke while out of the water, to gain confidence prior to entering the water. It may also be desirable to allow a more advanced swimmer to practice his or her form out of the water, for example, in situations where a swimming pool of the desired size (e.g., an "Olympic" sized pool) is not readily available, or where it would be useful for a trainer coaching the swimmer to closely follow the swimmer's activities to refine the swimmer's form.
Prior devices for facilitating swim training primarily rely upon mechanical expedients such as pull-strings, rotating handles and other similar means to define the arm and/or leg motion which is desired for the swim stroke being practiced. However, these devices all suffer from a common shortcoming in that each operates to emphasize the development and practice of swimming mechanics that emphasize (and develop) arm and shoulder pulling strength, or leg kicking strength. This is self-limiting since swimming does not rely entirely on muscle strength, but rather is heavily reliant upon the development of proper swimming technique and the ability to develop efficient swimming habits. This is equally so for the inexperienced swimmer, where it is important to ensure sufficient energy for satisfying basic distance requirements, or for the more experienced, competition swimmer, where even small differences in technique can mean the difference in overall outcome. The primary reason for this is that incorrect swimming form can cause the body to work harder than necessary, preventing efficient swimming and promoting fatigue despite the apparent strength of a given individual.
Correct freestyle swimming requires both concentration and practice, and the mastering of five elemental components. These components include hand entry, pull, body rotation, push and elbow recovery. The benefit derived from exercising proper form is that the energy expended with each stroke is utilized more effectively, to propel the body farther than if improper form is occurring. As a result, proper technique allows a person to swim for a longer period of time, and without fatiguing, a consideration which can in many cases be critical to outcome. The following discussion is provided to briefly describe the five elemental components which contribute to the development of proper freestyle mechanics.
Hand entry pertains to that part of each stroke where the hand enters the water, from overhead. During such entry, the hand should penetrate the surface of the water with the palm facing outwardly and with the thumb facing downwardly, to in essence "cut" into the water as smoothly as possible without slapping the water's surface or creating bubbles. This, in turn, operates to eliminate excessive drag during the hand entry phase.
The hand should continue to slide forward until a full extension is reached, which will also generally result in some rotation of the torso. At the point when the hand entering the water can reach no further, with the shoulder fully extended (causing the torso to begin a rotation), the opposite hand will be finishing the final stages of its stroke and will lift from the water, somewhere along the thigh. The entering hand will then begin its "pull" backward. During this pull, flexing of the hand and cupping of the water serves to develop a "paddle" for propelling the body forward. Also during the pull, the elbow is bent and the hand is carried from its point of full extension (somewhere in front of the shoulder) through an imaginary line in front of the chest, and then back toward the side of the thigh, to produce what is essentially an "S-shaped" motion.
The body will naturally rotate as the lead hand is extended to its limit. With the torso rotated, the head has the ability to surface for a breath. A simple turn at this point is preferred to avoid an unnecessary, jerky motion during breathing. A swimmer who does not rotate his or her body with each stroke will tend to swim flat on the chest (i.e., somewhat like a "barge"), and cannot cut through the water as efficiently as a swimmer who is constantly rotated onto the side (i.e., angled and propelled through the water like a "schooner").
When the pulling arm reaches the waist, the tendency is for the swimmer to take the hand out of the water while the elbow is still bent. However, most swimmers do not realize that a final "push" of the flexed hand down along the thigh utilizes the momentum of the paddle to propel the body even further.
The hand then exits the water, with the elbow raised high to allow the forearm and hand to dangle and rest completely as the hand is brought forward to prepare for the next entry. High elbow recovery is a key factor in strength conservation in the forearm and wrist muscles once the stroke has been finished and the hand is positioned above the surface (for re-entry).
Prior devices have tended not to encourage the user to perform a freestyle stroke using the correct technique, failing to support the goal of learning proper and efficient stroking. Such devices generally tend to fall into two categories, neither of which can encourage proper relaxation during the recovery portion of a freestyle stroke (i.e., when each arm leaves the water) or allow the user to adjust hand posturing (generally due to constant attachment of the user's hands to grips, handles or levers associated with the device).
One such category includes devices of the type having fixed hand grips, attached for example to retractable cables or cords. This would include devices such as are disclosed in U.S. Pat. No. 5,158,513 (Reeves), U.S. Pat. No. 4,948,119 (Robertson, Jr.), U.S. Pat. No. 4,844,450 (Rodgers, Jr.), U.S. Pat. No. 4,830,363 (Kennedy), U.S. Pat. No. 4,537,396 (Hooper), U.S. Pat. No. 2,434,542 (Borroughs) and U.S. Pat. No. 350,932 (Keating).
The second such category includes devices of the type having arm cranks or levers, which then requires some form of handle to be constantly gripped by the user (in order to rotate the arm cranks in a fixed elliptical pattern). This would include devices such as are disclosed in U.S. Pat. No. 5,282,748 (Little), U.S. Pat. No. 4,674,740 (Iams et al.), U.S. Pat. No. 4,422,634 (Hopkins), U.S. Pat. No. 3,791,646 (Marchignoni), U.S. Pat. No. 3,731,921 (Andrews, Jr.), U.S. Pat. No. 3,074,716 (Mitchel et. al.), U.S. Pat. No. 2,497,391 (Becker), U.S. Pat. No. 1,966,448 (Kabisius), No. U.S. Pat. 1,176,365 (Hartnett), U.S. Pat. No. 326,247 (Root) and U.S. Pat. No. 149,249 (Redfearn).
To properly teach and/or simulate a crawl or freestyle stroke, it is equally important to replicate correct body rotation. Two prior devices that work to provide torso motion would include the previously mentioned U.S. Pat. No. 4,674,740 (Iams et al.) and U.S. Pat. No. 5,158,513 (Reeves). U.S. Pat. No. 4,674,740 discloses a gimballing apparatus that allows the user's torso to rock from side to side. While achieving a rolling body motion, this design does not allow the user to achieve the full degree of rotation that is to occur in a freestyle stroke, particularly for the more aggressive swimmer. U.S. Pat. No. 5,158,513 also discloses a device that allows for torso motion to replicate the body rotation occurring in water, while swimming. However, such rolling motion is achieved by a "teeter-totter" rolling over a cylindrical support, which again limits the degree of rotation that is possible with such a device.
For these reasons, none of the devices disclosed in the above-listed patents can achieve or fulfill the purpose of correctly replicating the crawl or freestyle stroke, and it is therefore the primary object of the present invention to meet the need for such a device.
It is also the object of the present invention to avoid the need for the user's arms and hands to engage grips, handles or levers that can tend to develop motion throughout each stroke which is in some way not characteristic of an actual swim stroke.
It is also an object of the present invention to provide a swim training device which can correctly teach and/or replicate all five of the elemental components of a crawl or freestyle stroke.
It is also an object of the present invention to provide a swim training device which can correctly teach and/or replicate both the hand/arm motion and the body motion of a crawl or freestyle stroke.
It is also an object of the present invention to provide a swim training device which can correctly teach and/or replicate a crawl or freestyle stroke, and which is versatile, yet easy to use.